THE Sergeant remained silent, thinking his own thoughts, till we entered the plantation of firs which
led to the quicksand. There he roused himself, like a man whose mind was made up, and spoke to me
again.

`Mr. Betteredge,' he said, `as you have honoured me by taking an oar in my boat, and as you may, I
think, be of some assistance to me before the evening is out, I see no use in our mystifying one another
any longer, and I propose to set you an example of plain speaking on my side. You are determined to
give me no information to the prejudice of Rosanna Spearman, because she has been a good girl to
you, and because you pity her heartily. Those humane considerations do you a world of credit, but they
happen in this instance to be humane considerations clean thrown away. Rosanna Spearman is not in
the slightest danger of getting into trouble--no, not if I fix her with being concerned in the disappearance
of the Diamond, on evidence which is as plain as the nose on your face!'

`Do you mean that my lady won't prosecute?' I asked.

`I mean that your lady can't prosecute,' said the Sergeant.

`Rosanna Spearman is simply an instrument in the hands of another person, and Rosanna Spearman
will be held harmless for that other person's sake.'

He spoke like a man in earnest--there was no denying that. Still, I felt something stirring uneasily against
him in my mind.

`Can't you give that other person a name?' I said.

`Can't you, Mr. Betteredge?'

`No.'

Sergeant Cuff stood stock-still, and surveyed me with a look of melancholy interest.

`It's always a pleasure to me to be tender towards human infirmity,' he said. `I feel particularly tender
at the present moment, Mr. Betteredge, towards you. And you, with the same excellent motive, feel
particularly tender towards Rosanna Spearman, don't you? Do you happen to know whether she has
had a new outfit of linen lately?'

What he meant by slipping in this extraordinary question unawares, I was at a total loss to imagine.
Seeing no possible injury to Rosanna if I owned the truth, I answered that the girl had come to us rather
sparely provided with linen, and that my lady, in recompense for her good conduct (I laid a stress on her
good conduct), had given her a new outfit not a fortnight since.

`This is a miserable world,' says the Sergeant. `Human life, Mr.Betteredge, is a sort of target--misfortune
is always firing at it, and always hitting the mark. But for that outfit, we should have discovered a new
nightgown or petticoat among Rosanna's things, and have nailed her in that way. You're not at a loss to
follow me, are you? You have examined the servants yourself, and you know what discoveries two of
them made outside Rosanna's door. Surely you know what the girl was about yesterday, after she was
taken ill? You can't guess? Oh dear me, it's as plain as that strip of light there, at the end of the trees.
At eleven, on Thursday morning, Superintendent Seegrave (who is a mass of human infirmity) points out
to all the women-servants the smear on the door. Rosanna has her own reasons for suspecting her own
things; she takes the first opportunity of getting to her room, finds the paint-stain on her nightgown, or
petticoat, or what not, shams ill and slips away to the town, gets the materials for making a new petticoat
or nightgown, makes it alone in her room on the Thursday night, lights a fire (not to destroy it; two of her
fellow-servants are prying outside her door, and she knows better than to make a smell of burning, and
to have a lot of tinder to get rid of)--lights a fire, I say, to dry and iron the substitute dress after wringing
it out, keeps the stained dress hidden (probably on her), and is at this moment occupied in making